Yes, sounds reasonable if you put the roll over valve on the tank, then add your vent hose.
The roll over valve will prevent gas from sloshing into the vent hose. Once it does get into the tube the tank can build pressure until it pushes the gas out of the vent line.
The vent valve will need to be mounted vertically to work properly.
As for the gas vapors.. if the tank is a vented system you will smell gas fumes unless you add a charcoal filter or some other such device on the vent tube.
